Blow it out

Right now I have a cold. After blowing my nose for what seems like the millionth time, I wondered just how much mucus the nose produces during the average cold, and does its loss mean I lose any substantial amount of weight?

On average the normal nose produces 240 millilitres (about a cupful) of mucus every day. During a cold there is additional flow. Most of the mucus produced normally flows down the throat, and gets recycled within the body. During infection the nasal passage becomes constricted and therefore the inward passage of mucus is obstructed and it flows out through the nostrils.

There are other factors that increase the mucus flow, like the excessive formation of tears which can make their way to the nasal passage and mix with the mucus. Normal body processes lead to the formation of these liquids, and their loss or gain is compensated for ...

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